In a groundbreaking partnership with Autodesk, Dar has created a true pioneer in smart construction — converging the use of generative design, 3D printing, robotics, and artificial intelligence to reimagine how large-scale civil infrastructure can be built in the future.  The award-winning Smart Bridge is a proof-of-concept that construction — currently one of the world’s most dangerous and most polluting industries — can be smarter, more visually arresting, safer, more sustainable, and more innovative. At its core, the bridge is a two-metre interactive pedestrian bridge made from fibre reinforced polymer (FRP) and conceived and realised through state-of-the-art technologies and processes including generative design, additive manufacturing, and robotic technologies.

 
Generative design: Creating thousands of design concepts in mere hours
 
To design this unique structure, Dar used the generative design feature in Autodesk’s Fusion 360.
 
The generative design approach uses the power of artificial intelligence and the cloud to develop designs that conform to a given set of parameters and constraints, algorithmically generating hundreds or even thousands of potential design concepts in a very short amount of time.
 
Dar’s structural team then evaluated the merits of several interesting design concepts using multi-weighted criteria and giving considerable importance to the aesthetical value of the designed bridge.
 
Once the final bridge design concept was selected, the team moved to the detailed design phase, refining the design, conducting structural validation using third-party tools, and thoroughly examining the bridge’s structural integrity using specialised high-level structural FEA programs.

 
3D printing — additive manufacturing expands horizons in creative structures
 
Once the model for the pedestrian bridge was finalised, it was fed into a tool path optimisation software and to the robot for 3D printing. The manufacturing method used a robotic arm on which a customised end-effector is attached, capable of printing with both standard and sustainable materials, including the FRP material used for this particular bridge. The manufacturing system also relies heavily on an intelligent robot that uses closed-loop data feedback to learn what to print and where, to achieve the optimal bridge for the distance and loads required.

 
For the construction industry, the implications of 3D printing a bridge like the Smart Bridge are enormous.
 
For one, 3D printing and additive manufacturing give architects and designers more design freedom since 3D printing robots are not bound by the constraints of formwork and traditional construction methods: instead, these robots can build bespoke parts and sections and can make it possible to realise designs that shatter tradition, are visually stunning, and still retain all the properties of conventional structures.
 
A robot with 3D printing capabilities, such as the one designed for this project,  can also minimise the risk to construction workers  — either by eliminating dangers inherent in certain settings (such as working at height) or by enabling offsite construction.
 
Sustainability is another arena in which additive manufacturing wins out over traditional construction because it paves the way for the use of greener and more sustainable materials (though it works just as well with conventional materials such as concrete and metals), avoids formwork, and practically eliminates construction waste — one of the most pressing issues facing the construction industry today. The result is a structure with a far lower carbon footprint. In particular, the Smart Bridge project will take this feature one step forward, in the upcoming second stage five-metre bridge, which will use multi-recyclable materials chosen for their characteristics and sustainability.
 
Placing the nerves and setting the brain of the Smart Bridge — transforming a static structure into a smart, interactive one
The embedded and external sensors that give the Smart Bridge its name were installed in specific predetermined locations after the 3D printing process was complete. These sensors can be linked to an interactive artificial intelligence system that monitors the structural health and behaviour of the bridge in real time and collects environmental and structural measurements. The data feeds into the bridge’s “digital twin” to provide valuable insights throughout its lifespan and to inform future 3D-printed large-scale FRP structures.
 
Future horizons
 
The original project evolved into two separate research streams: a research stream dedicated to generatively designing and 3D-printing a smart bridge and a stream dedicated to developingDar’s Spark Design Assistant, an AI-driven algorithm that learns from Dar’s extensive bridge design experience to create and optimise new bridge designs.
 
The two-metre Smart Bridge is the first outcome of the first stream. The next step is to design and print a more advanced five-metre bridge with a more advanced design concept and recyclable material to augment the process to a larger span and monitor its behaviour over time.